In recent years, thinner and smaller semiconductor devices and their packages are increasingly desired. For that purpose, a flip-chip type semiconductor device has been broadly used, in which a semiconductor element such as a semiconductor chip is mounted on a substrate by flip-chip bonding (flip-chip bonded to a substrate). The flip-chip bonding is a mounting method of fixing the semiconductor chip to an adherend through bump electrodes formed on the circuit surface of the semiconductor chip so that the circuit surface faces the electrode formation surface of the adherend (face down). In the flip-chip mounting of the semiconductor element to the adherend, solder bumps, etc. provided on the semiconductor element are melted to electrically connect the two together.
After surface mounting, a sealing resin is filled in a space between a semiconductor element and a substrate for ensuring protection of the surface of the semiconductor element and connection reliability between the semiconductor element and the substrate. As this sealing resin, a liquid sealing resin (an underfill material) is widely used, but it is difficult to adjust an injection position and an injection amount with the liquid sealing resin. Thus, there has been proposed a technique of filling a space between a semiconductor element and a substrate using a sheet-like sealing resin (Patent Document 1).